It is no surprise that the scale of postal vote fraud in Birmingham was far greater than previously admitted. Everyone in Birmingham politics knows just how much the political system has been corrupted by the postal vote.

The big decline in postal vote applications shows that large-scale organised fraud can be reduced by tighter rules and the threat of police raids at dawn. But no amount of regulation can prevent the more insidious corruption of the democratic process that the postal vote is responsible for.

This has a particular impact on South Asian communities by reinforcing the grip of Biraderi politics - loyalties based on clan or kinship links, in which political conviction is secondary.

Classic patterns of migration, common to many communities, see new immigrants settle where they have already family or personal links. As a result, most of Birmingham's Muslim communities live in areas with others of a similar background. That background invariably lies in common village roots in Pakistan or Kashmir, with ties reinforced through marriage.

These strong community ties bring real benefits. They have provided an indispensable leg-up to newly arrived immigrants from rural areas as they navigate their way around their new country. The value of such support is incalculable, and is not readily forgotten. But the mutual obligations they are based on can be misused.

Biraderi loyalties have allowed influential figures in the community to claim control over blocks of votes that can run into the hundreds. These people can attempt to trade these votes for some favour or other: whether it is the acceptance of themselves or a relative on a mainstream party ticket, or just an increase in personal prestige.

Individuals claiming they have votes to trade have found willing buyers from mainstream parties ready to exploit this system. The result is that inner city areas, grappling with many social problems, end up with poor representation. Too often, councillors are selected more because of their ability to wield a block vote than their ability to represent the area. It is little wonder that a deep cynicism exists about the motivations of local politicians.

Biraderi loyalties remain important to many people, and these loyalties cannot be wished away. But the postal vote removes the essential safeguard of secrecy.

Postal votes are filled out in the "privacy" of one's own home. But it is not private when family members, candidates or supporters, can influence - subtly or otherwise - the way you complete your vote. This lack of secrecy is the reality for many people completing postal votes in Birmingham this week.

Community fixers may claim support from their biraderi, but no one can interfere with the secrecy of the polling station. A secret ballot means that loyalties to family and friends can be maintained in public, but political arguments can still win out in the real privacy of the voting booth.

The postal vote reinforces clan politics, encourages fraud, and damages democracy. In the context of Birmingham it severely undermines the principle of the secret ballot. The government's complacency is unacceptable. To restore confidence in democracy, the postal vote must be abolished.